1. Technical Field
The present disclosure relates to mobile communications, and more particularly to a mobile phone and a method for receiving calls.
2. Description of Related Art
A mobile phone can often connect to a third generation mobile communication network (called 3G network for short) including a plurality of base stations and a WIFI network including a plurality of access points. In the WIFI network, the access points assign different Internet protocol (IP) addresses for the mobile phone, so the mobile phone needs to change the IP addresses when the mobile phone roams from one access point to another access point. Thus, quality of communication of the mobile phone is affected.
In the 3G network, an operator of the 3G network assigns one IP address for the mobile phone, so the mobile phone does not need to change the IP address when the mobile phone roams from one base station to another base station. Thus, quality of communication of the mobile phone is assured.
Therefore, the mobile phone prefers to establish a voice over Internet protocol (VoIP) session with a remote phone over the 3G network instead of the WIFI network in order to assure quality of communication.
However, the 3G network is connectionless, so the mobile phone needs to turn on an always-on program, and periodically send connection data to the 3G network to keep a connection with the 3G network if the mobile phone wants to receive calls from a remote phone over the 3G network. Thus, the mobile phone consumes much power.